A nut plate is a small plate to which a fastener nut is secured. It is used in aircraft on walls which do not permit the use of a tapped opening. The nut plate typically includes a pair of fastener openings spaced diametrically apart on opposite sides of the nut. Fastener openings matching the fastener openings in the nut plate are drilled in a wall to which the nut plate is secured. The nut plate is positioned on the wall with its fastener openings in alignment with the fastener openings that were formed in the wall. Then rivets or other suitable fasteners are inserted into the aligned openings and secured in place to in turn secure the nut plate to the wall. A problem with this type of system is that there is wear at the rivets and fatigue in the wall through which the rivets extend.
The nut carried by the nut plate includes a threaded opening for receiving a threaded end portion of a bolt. It is necessary that the wall include an opening for the bolt as the bolt is installed from the side of the wall opposite the nut. Accordingly, when a nut plate is used, it is necessary to form at least three openings in the wall for each nut, one to serve as a passageway for the bolt and at least two others to serve as fastener openings to receive fasteners that are used to secure the nut plate to the wall.
A principal object of the present invention is to provide a substitute for the nut plate which requires the formation of a single opening in the wall. Other nut plate substitutes are known, such as a flare nut and nuts on a carrier having a tubular mounting portion which is intended to friction fit within a single opening. A problem with such fasteners is that they rotate in the opening and do not stay in place and/or the opening provides a fatigue problem area.
Prior art nut retainers are disclosed by U.S. Pat. Nos. 2,333,386, granted Nov. 2, 1943, to Howard J. Murphy, by U.S. Pat. No. 2,421,201, granted May 27, 1947, to Robert L. Hallock, by U.S. Pat. No. 4,768,907, granted Sep. 6, 1988, to Richard F. Gauron, and by Swiss Patent No. 482,929, granted Dec. 15,, 1969, to Josef Bucheli. Each of these patents disclose a type of gang nut assembly.